The invention relates to an electromagnetic fuel injection valve for internal combustion engines which includes a spin chamber located immediately upstream of the valve seat into which chamber the fuel enters via at least one inflow bore, all of which will be understood as the description progresses. These fuel injection valves are intended particularly for low-pressure fuel injection systems, in which the fuel is injected behind the throttle valve into the intake line of the internal combustion engine. In these systems, good fuel preparation is required so that the atomized fuel is carried along with the induced air and delivered in equal amounts to the branch tubes of the intake manifold which induce the mixture one after another. The maintenance of a continuous spinning motion of the fuel in the spin chamber located behind the injection port has the effect that even at the beginning of each opening valve stroke, there is spin energy available for a fine atomization of the fuel, which is of great advantage particularly in systems which have especially short injection pulses.
In known valves of the type referred to above, the closing body which monitors the injection port is conventionally embodied as a needle with a conical or frusto-conical tip. In this embodiment of the closing body, despite the spin constantly maintained in the spin chamber, it can happen that during the formation phase of an injection jet the spin does not transform pulses in the form of a spray jet, but rather that the jet leaves the injection opening in the form of a cord-like stream at first and thus tends to drip. Especially in systems operating in rapid cycles, this can mean that the ejected fuel is not atomized in the induced air stream in the manner desired and to the extend required for peak performance of the internal combustion engine.